Jost is one of the 32 provinces of Afghanistan. It is located in the southeast of the country. Its surface is 4,151 km². In 2007, its population was more than one million inhabitants. Its capital is the city of Jost. It was part of Paktiyā province. The province is mountainous and borders Pakistan in the east. Jost was the first city to be liberated by the communist government during the Soviet invasion of Afghanistan. In 1986, the US CIA built a terrorist training complex and a warehouse facilitated by Gulbuddin Hekyatmar in the province of Jost, which was subsequently used by Osama bin Laden to train Al Qaeda volunteers.
This site continued operations until it was bombed by order of President Bill Clinton in August 1998.